Quantitative NO-LIF temperature imaging in high pressure flames

Quantitative imaging of nitric oxide concentrations and temperature using laser-induced fluorescence (LIF) in practical combustion systems has attracted much attention in recent years [1]. Quantitative imaging measurements are of interest to optimize combustor efficiency and to minimize pollutant emissions [2]. However, at pressures above 10 atmospheres, attenuation of the excitation laser and fluorescence signal, broadening of the lineshapes and interference from molecular oxgen LIF cause problems when applying LIF techniques. Thermometry using LIF and quantitative NO planar LIF (PLIF) imaging are also affected by these problems and accurate measurements in highpressure environments are difficult to achieve. We report results of a new multi-line LIF temperature measurement strategy applied in a laminar high-pressure flame. Quantitative NO-LIF concentration imaging (1-60 atmospheres) is also reported and discussed.